Apparatus for supplying and mixing a liquid into a gaseous medium



April 21, 1959 E KRANTZ APPARATUS FOR SUPPLYING AND MIXING A LIQUID INTOA GASEOUS MEDIUM Filed June 1, 1955 FIG. 2.

, EVERT KRANTZ Y Y AJL'TYS- United States Patent APPARATUS FDR SUPPLYINGAND MIXING A LIQUID INTO A GASEOUS MEDIUM Evert Krantz, Stockholm,Swedemassignor to Aktiebolaget Svenska Flaktfabriken, Stockholm, SwedenApplication June 1, 1955, Serial No. 512,491

Claims priority, application Sweden June 5, 1954 4 Claims. (Cl. 261-16)The present invention relates to a device for supplying and spraying aliquid in a gaseous medium flowing in a channel. The need for spraying aliquid occurs within many technical fields. When spraying a liquid incon- 'nection with precipitation, liquid particles of the smallestpossible size are desired in order to cause an intimate contact with thedust particles. In a similar manner, in humidifying, cooling,dehumidifying, or other conditioning, a division of the liquid into verysmall particles is desired in order to obtain as great a contact surfaceas possible. The present invention relates to an apparatus for obtainingsaid efiect by simple means. The invention is mainly characterized inthat the flow of gasafter it first may have been free to expand-4scontracted abruptly, and that the liquid is conducted towards and isintroduced peripherally into the flow of medium at said contractionpoint, as a thin liquid film, which is caught and broken by thecontracted flow of gas and is mixed intimately with the flow of gas inthe form of small water particles.

A suitable apparatus for performing the invention consists of a supplyconduit for a gaseous medium, which conduit is provided with aconcentric expansion chamber, which is formed with an abrupt shoulderdefining a restricted orifice to the subsequent portion of the channel.The expansion chamber is provided with means for supplying the liquid,arranged in such a manner that the liquid forms a continuous liquid filmaround the inner periphery of the chamber, which runs along theconvergent envelope surface of said chamber, increasing in thicknesstowards the said shoulder and orifice to the subsequent portion of theconduit.

Other characteristics of the invention will be evident from thefollowing description and from the claims.

The invention will now be described more in detail with reference to theaccompanying drawings, in which:

Fig. 1 is a view in section of a conduit embodying the invention;

Fig. 2 is an enlarged detail of a portion of the apparatus shown in Fig.1; and,

Fig. 3 is a View similar to Fig. 1 showing a modification within thescope of the present invention.

Referring now to Fig. 1, a tubular supply conduit 1 is provided forsupplying gaseous dust-laden medium, the direction of flow of which isindicated by the arrow 10. The downstream terminal portion 2 of theconduit 1 is surrounded by an expansion chamber 4 which is arrangedconcentric with the conduit 1, this expansion chamber being defined by aside wall 5 and upstream and downstream, inwardly-extending end walls.The side wall 5 of said wall means converges in the direction of flow ofthe medium and terminates in the inwardly projecting, downstream endwall or shoulder 6, provided with a restricted discharge orifice 7,which orifice is in axial alinement with the downstream terminal portion2 of conduit 1 and is of less diameter than the downstream end of thewall means and of a diameter less than the smallest interior diameter ofthe converging side wall 5. As shown,

2,883, 1 6 7 Patented Apr. 21, 1959 "ice In the preferred form of myinvention, the downstream end of side wall 5 merges into the downstream,inwardly extending end wall 6 on a gradual, inwardly-extending curve asclearly illustrated in the accompanying drawing, which assists indirecting the liquid into contact with the gaseous medium flowingthrough discharge orifice 7. A discharge conduit 8 corresponding in sizeto the size of the orifice 7 constitutes a continuation of the supplyconduit 1.

Referring now to Fig. 2, it is seen that the liquid fed through theinlets 3 is caused to flow along the side wall 5 in a film by the flowof the gasous medium through the chamber. Since the side wall 5converges in the direction of flow of the medium, the film graduallyincreases in thickness as it approaches the downstream, inwardlydirectedend wall or shoulder 6. The end wall or shoulder '6, preferably ofinwardly-curved configuration, guides the film of liquid peripherallyinto the flow of the medium in the chamber, the flow at the orifice 7being abruptly contracted. This breaks up the liquid into :a very greatnumber of small liquid particles, which, as indicated by broken lines 9in Fig. 2, are mixed intimately with the flowing medium indicated by thefull line in Fig. 2.

As shown in Fig. 3, wherein parts similar to those shown in Fig. l aredesignated by similar reference characters followed by the letter a, anannular slot 11 may be provided between the side wall 5a of the chamber4a and the supply conduit terminal portion 2a. A separate gaseousmedium, such as air from the surrounding room, may be supplied by achamber 12 communicating with the slot 11 for the purpose of preventingcondensation and/or deposit of dust in the apparatus from the dustladenmedium introduced by the conduit 1. In the alternative, the chamber 12may be supplied with conditioned air, for example by a conditioner 13which decreases the viscosity of the liquid supplied by the inlets 3a.

While particular embodiments have been herein disclosed, it is notintended to limit the invention to this disclosure, but changes andmodifications may be made therein and thereto within the scope of thefollowing claims.

What I claim is:

1. Apparatus for introducing a liquid into a flowing gaseous dust-ladenmedium comprising means to supply the dust-laden gaseous mediumincluding a tubular supply conduit having an open, downstream end; wallmeans defining an expansion chamber surrounding that portion of saidsupply conduit adjacent the open, downstream end thereof and including aside wall and upstream and downstream, inwardly-extending end walls,said portion of said conduit projecting inwardly into said chamber adistance less than the length of said side wall, the side wall of saidwall means converging in the direction of flow of the dust-laden mediumand merging into the downstream, inwardly-extending end wall of saidwall means downstream from said open, downstream end of said supplyconduit, said downstream end of said wall means having a restricteddischarge orifice therein in axial alinement with said tubular supplyconduit, said discharge orifice being of less diameter than saiddownstream end wall and of a diameter less than the smallest interiordiameter of said converging side wall so as to provide an inwardlyprojecting shoulder in said expansion chamber surrounding said dischargeorifice and located substantially transverse to the direction of flow ofsaid dust-laden gaseous medium; and liquid supply means mounted in saidexpansion chamber about the inner surface of said side Wall andsurrounding the inwardly-projecting portion of said supply conduit toform a continuous liquid film covering the entire inner surface of saidconverging side wall so that upon flow of the gaseous medium from saidopen, downstream end of said supply conduit and through said expansionchamber and said discharge orifice, said liquid film flows along saidinner surface toward and into con tact with the shoulder formed by saiddownstream end wall, said converging side wall eifecting a gradualincrease in the thickness of said film toward said shoulder, saidshoulder directing and deflecting said thickened film inwardly intocontact with the gaseous medium flowing through said discharge orifice.

2. Apparatus according to claim 1 wherein the downstream end of saidside wall merges into said downstream, inwardly-extending end wall on agradual, inwardly-extending curve to assist in directing said thickenedfilm inwardly into contact with the gaseous medium flowing through saiddischarge orifice.

3. Apparatus according to claim 1 wherein the upstream end wall of saidwall means is provided with an annular slot positioned intermediate thatportion of said supply conduit surrounded by said wall means and saidliquid supply means for supplying a separate gaseous medium into saidexpansion chamber, said annular slot communieating with the surroundingatmosphere and said separate gaseous medium serving to preventcondensation and deposit in said chamber of dust from the dust-ladengaseous medium.

4. Apparatus according to claim 1 wherein the upstream end wall of saidwall means is provided with an annular slot positioned intermediate thatportion of said supply conduit surrounded by said wall means and saidliquid supply means for supplying a separate gaseous medium into saidexpansion chamber, and wherein there is a separate supply chamber influid communication with said annular slot and a conditioner inconnectionwith said separate supply chamber to condition the separategaseous medium supplied to said expansion chamber through said annularslot. 1

References Cited in the file of this patent UNITED STATES PATENTS1,430,912 McElvaney et a1 Oct. 3, 1922 2,104,315 Abramson Jan, 4, 19382,183,561 Hamblin. .Dec. 19, 1939 2,353,865 Armstrong July 18, 19442,436,319 Meyer Feb. 17, 1948 2,577,451 Clemens et al Dec. 4, 19512,657,024 Reinecke Oct. 27, 1953 2,760,821 Kenney Aug. 28, 1956

